[Chicken-janitors] #1604: fixnum arithmetic is ignored

[Chicken Trac]

#1604: fixnum arithmetic is ignored
----------------------+-------------------------------
 Reporter:  sjamaan   |                 Owner:
     Type:  defect    |                Status:  new
 Priority:  major     |             Milestone:  5.1
Component:  compiler  |               Version:  5.0.0
 Keywords:            |  Estimated difficulty:  medium
----------------------+-------------------------------
 As reported by chickendan on IRC:

 ```
 ;; csc -O5 -strict-types -fixnum-arithmetic: 7.964s
 ;; csc -O5 -strict-types:                    8.105s
 ;; csc -O5 -strict-types (and fx functions): 0.246s
 ;;; c/nim -O3 baseline:                       0.211s

 (define (fib n)
   (if (or (= n 0) (= n 1))
       n
       (+ (fib (- n 1)) (fib (- n 2)))))

 (let loop ((n 0))
   (when (< n 35)
     (print "n=" n " => " (fib n))
     (loop (+ n 1))))
 ```

 This program should use fixnum ops when declaring fixnum arithmetic.
 Also, when wrapping `fib`'s body in an `assume`, it still compiles to
 `C_s_a_i_plus` calls rather than `C_a_i_fixnum_plus` or even just
 `C_s_a_u_i_integer_plus`.

 I think we should take a look before releasing 5.1, the fact `fixnum-
 arithmetic` is ignored may not be a big issue, but it is rather worrying
 that the specializations aren't used.

--
Ticket URL: <https://bugs.call-cc.org/ticket/1604>
CHICKEN Scheme <https://www.call-cc.org/>
CHICKEN Scheme is a compiler for the Scheme programming language.